Backing Up Your Private Cloud
Private clouds are casting a shadow over backup and recovery operations. Customers we talk to are finding challenges to establishing the most efficient backup and recovery processes, and to finding solutions that are appropriate for cloud configuration. Often, backup and recovery are taking much longer than they need to (and therefore creating unnecessarily long RTOs) because of the backup approach that is used. Sometimes the private cloud architecture itself prevents the most efficient form of backup and recovery. This post will cover how to time-efficiently back up and recover in a private cloud, and how to architect the cloud to support it.
You can use either primary virtual backup method in a private cloud: agent-based backup or image-based backup. Image-based backup provides particularly strong time-saving advantages in the private cloud environment.
Let's look at how to recover a VM that was backed up using an agent in a private cloud. The agent backs up data in the guest, not at the image level. To recover, first you deploy a VM from a stored template, or configure one from scratch. Next, you get the OS up and running, then applications can be reinstalled and their settings adjusted. Only now are you ready to restore the data from the backup agent. Finally, the restored VM has to be imported back to the cloud layer so it can be available to users.
Contrast this approach to image-level backup. By backing up at the image level, you capture data, applications and the OS in one pass--and can restore them all in one step. Private clouds still create challenges for restoring virtual images. Typically the backup software is not aware of the private cloud platform, so virtual images will need to be restored to the hypervisor then imported to the private cloud.
Think about how these different recovery processes would make a difference in your recovery time. Image-based backup enables much tighter RTOs, which is a real advantage for DR programs.
Platform Considerations
For guidance on how to architect backup and recovery in a private cloud, think about why private clouds are being created in the first place. Usually, it is to provide self service to users so the enterprise can scale up and down based on demand. Therefore, backup and recovery should be integrated at the cloud layer--not at the OS or hypervisor level--so the self-service portal provides data protection options for clients on request. Integrating at the cloud level also makes it easier to allow clients to automatically restore some things while having to make requests for others.
Where you will integrate backup and recovery into your private cloud has implications for the solution you select. Think of your private cloud as software-as-a-service. You want solutions that can plug into the service to enhance its functionality and value. There is an example within the Salesforce.com ecosystem. Force.com allows third-party software to integrate with and be controlled through Salesforce.com. Solutions can be tightly integrated and easy to manage. You can do the same with backup and recovery in a private cloud.
If the third-party backup solution has appropriate APIs, you can set up headless (no separate interface) backup and recovery solution in the private cloud. The backup vendor then simply needs to provide a plug-in to the cloud platform to automate and control backup from the cloud layer. For example, the plug-in could allow self-service users to choose what to backup and how often, and could be set to automatically approve requests or forward them to an administrator for review. Once the backup request is approved it can execute automatically.
No one vendor has the total solution today. However, those solutions are looming and likely to hit the market in the next year or two. Don't let that stop you from pursuing private cloud initiatives, because reliable backup options are available. VMs can be backed up and restored to the cloud using either agent- or image-based backup. So go ahead and move to the cloud, just think about how to back it up beforehand so you don't waste time.
Posted by Jason Mattox on 11/17/2010 at 12:49 PM